Device for supporting a coated abrasive

ABSTRACT

A device for supporting a non-porous coated abrasive while performing work therewith. The device includes numerous miniature suction cups which grip the non-porous back side of a coated abrasive.

United States Patent 11 1 Kitts, Jr.

[ 1 Aug. 26, 1975 1 DEVICE FOR SUPPORTING A COATED ABRASIVE [76] Inventor: William H. Kitts, Jr., 3761 Earls Ct., Memphis, Tenn. 381 18 [22] Filed: Jan. 24, 1974 [21] Appl. No.: 436,072

[52] US. Cl 5l/362; 51/391 [51] Int. Cl. B241) 9/10 [58] Field of Search 51/170 T, 362, 391, 392,

Primary Examiner-James L. Jones, Jr. Attorney, Agent, or Firm-John R. Walker, 111

[ 5 7 ABSTRACT A device for supporting a non-porous coated abrasive while performing work therewith. The device includes numerous miniature suction cups which grip the non- [56] References Cited porous back side of a coated abrasive.

UNITED STATES PATENTS 1 Cl. 7 D F. 1,228,649 6/1917 Childs ..51 235 raw'ng gums I 1 J 1 1 1' i 1/ 1 1 1 I 1 1 i. .3 Q1. 43 .51 l W FIG. I

PATENTED AUBZB 1975 FIG. 2

FIG. 3

, ,976 PATENTED AUEZBIQTS 3 900 FIG. 4

DEVICE FOR SUPPORTING A COATED ABRASIVE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to the field of devices for supporting coated abrasives.

2. Description of the Prior Art Applicant has knowledge of the following patents: Lorenz, U.S. Pat. Nos. 1,291,572; 1,353,967; and 1,355,345; Smul, US. Pat. No. 2,499,933; Stiller, US. Pat. No. 3,071,886; and Cowley, US. Pat. No. 3,089,294. None of the above patents disclose or suggest applicants device. Applicants device is directed toward solving a prevailing problem which was recognized at least as early as 1917 as evidenced by the above-mentioned 572 Lorenz patent and the following is a quote therefrom: Ordinarily the abrasive discs are glued to the metal grinding discs. This has to be done carefully in order that the surface will remain flat. It also consumes considerable time in attaching and drying. When a new disc is attached the old one must be removed, and the metal discs must be cleaned before attaching a new abrasive disc. It should be pointed out that it is still common practice today to use various adhesives for attaching the coated abrasive to the abrasive supporting structure or the use of grit cloth held to the surface by pressure during the sanding operation. In the case when adhesives are used, it is time consuming and there is additional cost involved. Also, remov' ing the coated abrasive from the support structure often is accomplished by using a solvent to dissolve these adhesive materials. This is time consuming and often the entire head or pad is simply replaced. Certain problems are created when attempting to use solvents to remove the coated abrasive. More specifically, solvents generally are a fire hazard and/or hazardous to ones health when breathing the vapors therefrom. Therefore, the use of solvents for industrial use is generally discouraged and procedures or new concepts which eliminate such use are advantageous.

Several problems are prevalent in the field of painting automobiles or the like, a few of which are: First, prior known devices for holding a coated abrasive are unsatisfactory resulting in the workman reluctantly holding the coated abrasive in his hand while performing work therewith. This practice is extremely abusive to the hands of the workman, e.g., the hands engage sharp objects and the abrasive itself is a constant source of irritant. Secondly, most of the work performed in this field is water sanding, i.e., the workman uses water as a wetting and flushing agent. Accordingly, the problems are compounded by the coated abrasive being slippery and much more difficult to grip. A third problem is that a true planar surface for supporting the coated abrasive is unacceptable since substantially the entire surface of an automobile is contoured. Additionally, a preferred procedure in sanding of this type is to feather edge the paint around a blemish leaving a slight depression or irregularity to the contour. Accordingly, the workman usually uses his fingers to urge the coated abrasive into these slight depressions. It should be mentioned that it is not feasible to wear gloves while sanding an automobile finish. In fact, it can accurately be stated that the hands of an automobile finisher generally are tough and sore most of the time.

Another type of sanding well known to those skilled in the art is referred to as oil sanding and the same problems enumerated above which pertain to water sanding are applicable to oil sanding. Actually, the oil makes the coated abrasive even more slippery or more difficult to grip than does water.

Typical coated abrasives being marketed, at the present, generally comprise a porous web having the obverse side thereof coated with an abrasive. This type of coated abrasive, whether it be sandpaper, emery cloth, grit cloth or the like, cannot effectively be gripped by suction cups. However, a non-porous coated abrasive, referred to as mylar coated abrasive, is presently available but it is extremely costly. Therefore, it is not feasible to use mylar coated abrasive for general purposes, e.g., particularly while performing the task of sanding automobile finishes or the like. It should be pointed out that mylar coated abrasive comprises a non-porous web of mylar plastic which has an abrasive substance coating the obverse side thereof.

Applicant also has knowledge of a tool characterized by a soft foam rubber pad attached to a hard plastic back-up pad. The coated abrasive used with this tool is a screen grit cloth. This combination is usually used with a pneumatically driven motor. There is no mechanical connection between the pad and the coated abrasive. Pressure applied to the pad urges the pad and coated abrasive against the work surface and friction is the only thing that prevents the pad from slipping from the coated abrasive. Obviously, with water and oil sanding, particularly on vertically disposed surfaces, extreme care must be taken to prevent the tool from slipping away from the disc shaped grit cloth or from the latter being flung away from the work surface. Therefore, this concept also leaves something to be desired.

SUMMARY OF THE INVENTION The present invention is directed towards overcoming the disadvantages and problems relative to previous devices for holding coated abrasives. One object of the present invention is to provide an inexpensive coating abrasive attachable to a device which depends upon suction for its gripping action. A coated abrasive suitable for the purpose herein disclosed includes treating the abrasive with a sealant substance or shellac which is suitably applied to the backside thereof, thus facilitating optimum suctional gripping action.

The concept of the present invention is to provide a device for supporting a non-porous coated abrasive while performing work therewith. The device includes numerous miniature suction cups which grip the nonporous backside of the coated abrasive. It will be appreciated by those skilled in the art that in the span of approximately two seconds, the worn non-porous coated abrasive can be removed from the device herein disclosed and replaced with a new sheet of non-porous coated abrasive. The time factor involved in accomplishing the above change is an important feature of the present invention. This is particularly advantageous in high volume mass production of large surfaces that must be sanded.

The device herein disclosed is intended to encompass both a hand held embodiment and a power driven embodiment, i.e., the power driven embodiment being either a disc sander or an orbital sander. The advantages of the present invention are:

First, the user can now accomplish the task of sanding automobile finishes without holding the abrasive in his hands. Accordingly, the hands of the automobile finisher no longer need be sore from the constant abuse as described above.

Secondly, the problem of the abrasive being difficult to grip while performing in water or oil sanding is obviated. In fact, the more oil or water used in the flushing process the greater is the gripping power of the miniature suction cups.

Third, the resiliency of the suction cups and the pressure applied to the device during the sanding operation enables the entire area of the coated abrasive to be uniformly urged against the contoured work surface irrespective of minor irregularities that may exist on the surface of the work piece. In other words, the device enables the user to accomplish the sanding operation with exceptional results. In fact, these results approach the previous procedure of holding the coated abrasive in the hand of the user and using his fingers to urge the coated abrasive into slight depressions, i.e., the individual suction cups act as little fingers to urge corresponding portions of the coated abrasive into minor depressions or the like.

Fourth, the coated abrasive is fastened very securely with the miniature suction cups and it is not flung away from the work surface and neither does it slip from the device while performing work therewith.

Fifth, the device enables the operator to sand more accurately in close or substantially inaccessible areas without tearing the abrasive.

Sixth, the device allows the user to sand vertically disposed surfaces with greater ease and with total assurance that the coated abrasive will not become disengaged from the device.

Seventh, the coated abrasive can be changed on the tool in a couple of seconds.

Eighth, the usable life span of the coated abrasive is increased since it is supported over substantially the entire surface thereof. Additionally, in water and oil sanding, the flow of the flushing fluid can now freely pass over both sides of the coated abrasive keeping the coated abrasive cooler during the sanding operation, i.e., a space exists between the coated abrasive and the main body of the device enabling the fluid to pass over the back side of the coated abrasive.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view of the device of the present invention for supporting a coated abrasive.

FIG. 2 is a sectional view taken as on the Line IIII of FIG. 1.

FIG. 3 is a side elevational view of the device of the present invention showing a coated abrasive attached thereto and suitably engaging a work piece.

FIG. 4 is a top view of an alternate embodiment of the device of the present invention.

FIG. 5 is a sectional view taken as on the Line V-V of FIG. 4.

FIG. 6 is a planar view of a coated abrasive.

FIG. 7 is a sectional view taken as on the Line VII- -VII of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT The device 11 of the present invention is intended to effectively support a non-porous coated abrasive 13 while performing abrading or sanding work therewith.

The coated abrasive l3 suitable for engagement with the device of the present invention includes a flexible porous web, as at 15 in FIG. 7 of the drawings, having an abrasive substance, as at 17, covering the obverse side 19, and a poriferous reverse side as at 21 in FIG. 7 of the drawings. The coated abrasive 13 includes sealant means or shellac as at 23 in FIG. 7 of the drawings, covering the poriferous reverse side 21 of the coated abrasive 13 for substantially closing the pores thereof to establish a smooth non-porous surface, as at 25, for facilitating optimum suction attachment thereto. The shellac 23 or other sealing substances are waterresistant for adequate periods of time to allow the use of water for water sanding in a manner obvious to those skilled in the art.

The device 11 includes a main body member 27 having a substantially planar surface, as at 29. The device also includes a plurality of outwardly projecting miniature rubber suction cups, as at 31, fixedly attached to the planar surface 29 for releasably gripping the nonporous or reverse side 25 of the coated abrasive l3 and for releasably and effectively supporting the coated abrasive 13 while engaging the obverse side 19 thereof or the abrasive substance 17 coating against a work piece W as the device 11 is moved about to perform abrading work therewith.

The coated abrasive 13 includes a pair of remotely disposed first portions, as at 33, 33 in FIG. 3 of the drawings, and it may clearly be seen therein that the many suction cups 31 engage only the first portions 33. The abrasive 13 also includes an intermediate or second portion 35 for reasons yet to be disclosed. The device 11 includes a plurality of resilient leg members, as at 37, for respectively supporting the miniature suction cups 31 in a manner about to be described.

The inner ends of the leg members 37 are fixedly attached to the substantially planar surface 29 with the plurality of suction cups 31 respectively being fixedly attached to the outer ends thereof, i.e., the suction cups 31, the legs 37, and the surface 29 preferably being integrally formed. The resilient leg members 37 are individually compressible to shorter lengths as pressure is applied to urge the device 11 towards the work piece W whereby the entire area of the first portions 33 of the coated abrasive 13 are urged against the work piece W with substantially equal pressure irrespective of limited or minor irregularities that may exist on the surface of the work piece W.

The device 11 preferably includes a protuberant member, as at 43, for engaging and selectively urging the second portion 35 of the coated abrasive l3 firmly against the work piece W in a manner about to be described. The protuberant member 43 is fixedly attached to the substantially planar surface 29 in any well known manner as by being integrally formed therewith. From FIGS. 2 and 3 of the drawings it may clearly be seen that the protuberant member 43 projects a predetermined distance outwardly from the surface 29. The resilient leg members 37 are suitably constructed so as to have predetermined uniform lengths thereto when being slightly compressed so as to normally urge the first portions 33 of the coated abrasive 13 to effectively engage the work piece W independently from the second portion 35 thereof as minimal pressure is being applied to the device 11. The second portion 35 is caused to engage the work piece W with ever increasing vigor as the pressure being applied to the device 11 is increased. It should be understood that if desired, the protuberant member 43 may be omitted from the device 1 1. In other words, additional suction cups 31 may be added to the surface 29 to engage the second portion 35 of the coated abrasive l3. 7

The device 11 includes a bulbous member, as at 45, fixedly attached to the main body member 27 as best shown in FIGS. 1-3 of the drawing. It will be understood that bulbous member 45 and main body member 27 may be integrally formed or molded from the same piece without departing from the spirit and scope of the present invention. The bulbous member 45 is suitably adapted in shape to facilitate being firmly gripped in the hand of a user as he manually moves the device 11 about.

The main body member 27 and the suction cups 31 are preferably formed from neoprene rubber or the like so that petroleum products, such as oil, used in oil sanding will not deteriorate the device 11. Also, it could be other materials such as natural rubber.

From FIGS. 4 and 5 of the drawings it may be seen that an alternate embodiment of the device is herein disclosed and is character referenced therein by the numeral 11'. The device 11' may be circular in shape as shown in FIG. 4 but is not to be limited to this configuration. In other words, the device 11 may be rectangular or whatever without departing from the spirit and scope of the present invention. The device 11' is very similar to the principal embodiment, therefore, similar or like structure pertaining to both embodiments will be characterized by identical numerals. The device 11' is further characterized by including means, as at 47, for attaching the main body member 27 to a motor, as at 49, whereby the device 11' is power driven as a user manually moves the device 11 about.

It should be understood that the means 47 as depicted in FIGS. 4 and 5 of the drawings is intended to show only one manner in which the device 11 may be power driven. In other words, it is anticipated that the device 1 1 may be power driven in any manner according to the current state of the art, i.e., including rotating sanders and orbiting sanders, etc.

Therefore, the foregoing notwithstanding, the attaching means 47 includes a concentrically disposed shaft, as at 51, which may conveniently be adapted to various drill motors, as diagrammatically depicted and referenced by the numeral 49. The shaft 51 is fixedly attached to the main body member 27' in any well known manner as by being integrally formed therewith. It may be desirable that portions of the main body member 27 be more flexible than other portions, i.e., in the event the device 11 is intended to be a rotating disc. Accordingly, the main body member preferably tapers outwardly toward the periphery thereof as at 53. Additionally, the main body member 27' preferably is formed from a flexible substance, such as neoprene rubber or the like, whereby it may be urged to conform to various shapes as the pressure being applied to the device 11 is varied. In this regard, the suction cups 31 also preferably are formed from neoprene rubber or the like so that petroleum products, such as oil, used in oil sanding will not deteriorate the device 11.

It should be understood that while the invention has been described and illustrated with respect to preferred embodiments thereof, it is not to be so limited since changesand modifications may be made therein which are within the full intended scope of the invention.

I claim:

1. The combination with a flexible sheet of a coated abrasive having an obverse side covered with an abrasive and a reverse side treated with a sealant to close the pores thereof, said coated abrasive including first and second portions, of a device for releasably supporting said flexible sheet of coated abrasive while performing abrading work therewith, said device comprising a main body member having a substantially planar surface, a plurality of outwardly projecting miniature suction cups fixedly attached to said substantially planar surface for engaging and gripping said first portion of said coated abrasive and for releasably gripping thenon-porous reverse side of said sheet of coated abrasive and for firmly supporting said sheet of coated abrasive while engaging the obverse side thereof against a work piece as said device is moved about to perform abrading work therewith, a plurality of resilient leg members for respectively supporting said miniature suction cups, the inner ends of said leg members being fixedly attached to said substantially planar surface of said main body member with said suction cups respectively being fixedly attached to the outer ends thereof, and said resilient leg members being individually compressible to shorter lengths as pressure is applied to urge said device towards the work piece whereby the entire area of said first portion of said coated abrasive is urged against the work piece with substantially equal pressure irrespective of minor irregularities within limits that may exist on the surface of the work piece, and a protuberant member for contiguously engaging and selectively urging said second portion of said coated abrasive firmly against the work piece, said protuberant member being fixedly attached to said substantially planar surface of said main body member and projecting a predetermined distance outwardly therefrom, said resilient leg members having predetermined uniform lengths thereto when being slightly compressed to normally urge said first portion of said coated abrasive to effectively engage the work piece with ever increasing vigor as the pressure being applied to said device is increased. 

1. The combination with a flexible sheet of a coated abrasive having an obverse side covered with an abrasive and a reverse side treated with a sealant to close the pores thereof, said coated abrasive including first and second portions, of a device for releasably supporting said flexible sheet of coated abrasive while performing abrading work therewith, said device comprising a main body member having a substantially planar surface, a plurality of outwardly projecting miniature suction cups fixedly attached to said substantially planar surface for engaging and gripping said first portion of said coated abrasive and for releasably gripping the non-porous reverse side of said sheet of coated abrasive and for firmly supporting said sheet of coated abrasive while engaging the obverse side thereof against a work piece as said device is moved about to perform abrading work therewith, a plurality of resilient leg members for respectively supporting said miniature suction cups, the inner ends of said leg members being fixedly attached to said substantially planar surface of said main body member with said suction cups respectively being fixedly attached to the outer ends thereof, and said resilient leg members being individually compressible to shorter lengths as pressure is applied to urge said device towards the work piece whereby the entire area of said first portion of said coated abrasive is urged against the work piece with substantially equal pressure irrespective of minor irregularities within limits that may exist on the surface of the work piece, and a protuberant member for contiguously engaging and selectively urging said second portion of said coated abrasive firmly against the work piece, said protuberant member being fixedly attached to said substantially planar surface of said main body member and projecting a predetermined distance outwardly therefrom, said resilient leg members having predetermined uniform lengths thereto when being slightly compressed to normally urge said first portion of said coated abrasive to effectively engage the work piece with ever increasing vigor as the pressure being applied to saiD device is increased. 